Gear-cutting machine



p 7, E93? E. L. FQCKETT GEAR CUTTING MACHINE 4 sheets-sheet 1 Filed Nov.2 1923 rnasi Metil .'Pll 7, 1931.! E. l.. FlcKl-:T'r 1,795@

` `GEAR CUTTING MACHINE Filed Nov. 2 1928 4 Sheets-Sheet 4 will be.better understood from a descriptionof the selected embodiment, for thepurposes Patented Apr. 7, 1931 UNITED STATES PATENT oFEIcEgf ERNEST L.ETCKETT, oE 'EITCHEUEG, MASSACHUSETTS, 'ASs1GNoE, EY' MESNE As-VvSIGNMENTS, To scUELooK GEAE ooEPoEATIoN, or NEW YORK, N. Y., A com vPVOBATION OF NEW YORK GEAR-CUTTING MACHTNE Application flied November 2,192s. serial Noysiafsas.`

, The present invention has for an object to-provide an improved gearcutting machine.

Spiral bevelv gears may be cut to provide teeth kof substantially equalwidth throughout their length with spaces of varying width or they maybe cut to provide spaces of sub-y stantiallyequal width with teethoffvarying width vor' other provisionkcan be made fork making allowancefor' the variationzindiameterat different points of the gears. Thepractical limitations of the machines? used determine in part the formof the teeth.l

The present inventionprovides in its preferred form a machine havingseparate cuttversjwhich can be operated, to some extent, independentlyof each other to cut the 0p-y posite vfaces of the' teeth. Thisarrangementy makes possible the desired shaping of the teeth'withoutlimitations that' are imposed when onecutter must simultaneously engagevopposite tooth faces. The machine to beparticularly described isdesigned normally to cut gearteeth having the form of an Archimedeanspiral, and the two cutters andthe cutter feeding mechanism can be soadjusted that the-oppositefaces of the teeth will cut on spirals whichapproach each other to pro-- vide teethv having -a desired taper. IThemachine maybe adjusted and the. cutters so shaped that each cutterforms complete teeth'. l y

The vnature and objects of the invention of which description referenceshould be had toathe accompanying drawings kforming 'a part hereofandinwhichf l er Figure 1 is la plan view of a gear cutting machine:embodying the invention, i

beingwshown in section, j j v Figure 3 is a view infront elevation, someparts being brokenv away, i y

Figurel is a detail sectional viewA taken on the line IV-IV of Fig. 1,

Figurel 5 is a detail View of one ofqthe critters, and

Figure 6 is an illustrating theinvention comprises a central horizontalwork Spindle `5 arranged to carry a'` workblank 6 at its forward end andtwo ver-v` tical cutter spindles 7, l8 arrangedv to, carry cutters 9, 10at ,theirupper ends .The two. cutter spindles may be driven more or,less

faces ofthe gearteeth. If desired each cut termay be provided withcutting teethy ar-A ranged in pairs, as shown in Figures 5 and 6, sothat one tooth ofa pair can rough Y,and

enlarged Viewl of `a i section .s of the edge of'one of the ,cutters iThe machine shown for the purposes of cof another iinishthegear, theroughing tooth, of

course, being slightly in advancefof the fin-1 ishing tooth. .f

By so arranglng the cutters that one cuts `one side. of each gear toothand thev other cuts the otherzsideof eachitooth, it is possible to soposition the cutters that they' will both cut in ahorizontal planethrough ther l `axis ofthe blank and with such a feeding movement thatboth sides of the gear teeth;v

will be cut to the desired curves. The cutterA spindles are mounted oncarriages 11 and 12 for movement along the face of the gear from ltheperiphery. toward the center andl these carriages are in turnSupportedon saddles 13, ltwhich are angularly adjustable on the ybedi.of the machine and `arranged to vberclamped in adjusted position bybolts 15. y Inl opera-l tion the worky spindle is lrotatedin onedirectionor theother as 'itis desired to cut a right or left spiralgear. If desired,instead n of reversing the ldirection of rotation ofthe workblank right and left'hand spiral gears n may be cut by reversingthe direction offeed Figure 2 is a view in side elevation, some of theCutters along the face of the gezin 'one parts being broken away vandsome parts being cut by moving the cutters from the periphery *towardthe-center, and vthe other being cut bymoving-thefcutters fromthe .y i

and'wprk spindle,` respectively. The machine shown is designed and setup for cutting left hand spiral gears and, therefore, the spindle isdriven in the direction indicated Y by the arrow in Fig. 1. For the sakeof simplicity of disclosure no reversing mechanism is showmbutit will beunderstood that a reversing "mechanism may readily be pro# vided if itisv desired to use the same vmachirle for cutting both right and leftspiral gse.,

The cutters are rotated and fed along the face of the ,work by powertaken from the main power shaft 17. The gearing fer driving the cutterscomprises a shaft 21 (Fig. 1) extending longitudinally of the machineand driven from the main power shaft 17 by change speed gears "'22,z 23,24', 24'; shaft 2 5 and miter gears-26TA"ver`tical shaft 27 nieulntedfin the' wsaddle 14 in thelin'e of the 2 9 aXi'sA about which'the' saddlev 'rotatably adjustable 'is Vdriven from thefhori'zont'alshaft 2 1v'ly`neansoffn1iter gears v28. The cutter spindleSis'dr'ivenfroni the shaft 27 through afeiitable train fgearing which issliown 2Q as"cn lrising"mitery Vgears 30, horizontal shaft `31,'"1nitergears 32, verticali'shaftl 33; ruiter gears 34`,Land horizontal shaft35,/with aworrnfSG on'shaft 3,5 engaging a worm wheel 37'611the'ciitterspindle 8`,``all of which gearing' ifsQc'arriedin the Vsaddle14e. The com-V panion'ctter spindle 7"'o'f the saddlev 13 issiii'larlyidriven' similar gearing andreceives"l` power rvfrom thel'vertical'"shaft 27 through a pair of spur gears 40 on the verticalshafts 27 and 27. The corresponding gears ndfshaft's'of the saddle 13are for the Inostpart designated by the same characters dule -14, butwahffpr'imejexpnlas ""The'farriagefed nge ifs drives eem the sljaft`17but-"preferably by 'a drive mecha-'i 1i s iwhiych is ihdependentof thecutter drive. Afs '"'shown, a transverse shaft: 43 is" drivenffom'fthmae power staaf 17 'by 'Change epee-51 gears/ 1.4,- isyle, 47:"A @giammai i'isdriven "in one directionfcr` the cut 'n feedfrfom thetransverse'shaft the` corresponding shafts and gears of the..

trolling the feed of the cutter and can be of any desired character. Ifgears of other than Archimedean spiral curve are to be cut, this camscrew will be designed to give the required motion, or a cam of anysuitable type may be substituted.

The feed v'screw' 63 isn driven from the vertical shaft through asuitable train of gearing which is shown as comprising miter gears 65,horizontal shaft '66, Initer'"gearsV 67 vertical shaft 68 and ruitergears'l; The earriage 12 is similarly operated from the 'same source ofpower through a train of mechanism which is designated by the samereference characters but with prime exponents. The, shaft 60 and theshaft 60 are connected by'spu'r gears'70.' 'The feed screw`63` orcafm,if' itisV not` a `true screw,wllv ordinarily have the same pitch as thefed screw 63. The' 'werk spindle is longitudinally Inovable' toward' andfrom the'cuttersto vpermit adjustment ofthe work 'relative' tothe cut-yters.V As' shown 'in the drawing, the he'ad'sto'cl of the machine isadjustable' on 'the'bed and may be moved by means of'an adjusting screw7 5f 'The horizontallongitudinal 'shafts'21'and 510 are splinedandlongitudinally movable within the several gears in the headstock and inthe V clutch and pulley thereon topermit this movement of'the headstock;

It will'be noted that one of the cutters is inverted to correspond tothe movement'of the work. The cutters may beof any suitable sliapel Thecutter shown in Fig.` `5 iss'o de` signed that the cutting edges foropposite sides of the tooth faces lie in substantially the same plane."A'In setting up the machine'the Cutters Should'be adjusted vertically en'their' spindles" te suitable positions having due regard tothe cuttingeffect desired. Ordinarily all cutting edges should liesubstantially'ina plane throughy the axis vof'the gear to be cut.

lThe provision oftwo cutters-as illlristratedV makes possible theshaping o f the'teethof the'cutter more eifecti'vely'to meet requirefments. ""VVhether 'the teeth are cut on 'an Archimedean spiral orlogarithmic orothei' spiral thedrive and feed mechanism whendesi'red'may beV so. related that each cutter cuts on ra spiralterminating at the apeX'as distinguished from 'an arrangement in whichvthe opposite tooth faces are cut on lines substantialglyparallel. toeach other. Accordingly better meshing gears may be provided- Theforegoing' description of a particular embodimenty is illustrativemerely and is not intended as. defining. the limits 0 5 the. inventioniI claim- 1. A gearcuttingv machine fory use in cutting spiral bevelgears comprising, a gear blank Supporting Spindle, e Pai-.1" Of. Cuttershaving their aires atan Kangle to,I said spindle, meansV for rotatingthe cutters and thefgear" blank' at speeds vproportioned aceording toige the number of teeth on said cutters and blank in such relation toeach other that each tooth of each cutter moving in the direction of atooth space on the blank passes into and out of said space duringrelative rotation of said cutters and blank and means for feeding thecutters relatively along the face of the blank.

f 2. A gear cutting machine as defined in claim l in which the cuttersare mounted in guides adjustable angularly relative to the gear blanksupporting means.

3. A gear cutting machine as dened in claim 1 wherein the cutters aremoved along the face of the blank by independent feeding means.

4:. A gear cutting machine for cutting spiral bevel gears comprising, incombination, a rotatable Work carrying spindle, a pair of carriagesmovable parallel to oppo site sides of a Work blank carried on saidspindle, rotatable cutting tools carried by said carriages for cuttingopposite faces of gear teeth on said blank, and means for simultaneouslyrotating said spindle and said cutting tools to cut teeth on said blank.

5. A gear cutting machine for cutting spiral bevel gears comprising, incombination, a rotatable Work spindle, a pair of cutting tools movablealong opposite sides of a blank carried by said spindle to cut gearteeth thereon, a carriage in which each cutting tool is carried, meansfor adjusting the angular direction of movement of said carriages, andmeans for simultaneously driving said Work spindle and shifting saidcutting tools along said blank.

In testimony whereof, I have signed my name to this specification this9th day of Y October, 1928.

ERNEST L. FICKETT.

